Workplace noise and hearing loss: why annual testing matters

Why noise-induced hearing loss is missed

Noise-induced hearing loss progresses gradually, starting at high frequencies used to understand speech in background noise. Workers often notice only once hearing has declined significantly, and existing damage cannot be reversed.

Regular hearing testing reveals the trend before workers notice it, giving the safety team time to act.

How the test works

Pure-tone audiometry presents tones at different frequencies and decreasing volumes; you press a button when you hear them. The result is a hearing chart for the left and right ear.

Comparing with previous results lets a doctor see whether changes are greater than expected from age alone, which is the key surveillance question.

How to prepare

The most important step is resting from loud noise for at least 14 hours before the test, as standard practice, because continuous noise causes temporary threshold shift and inaccurate results.

• Avoid noisy work areas and loud music before the appointment
• Clean your ears gently; do not dig deep or use ear oils before testing
• Tell staff about fluid in the ear, infection, hearing aids or ear surgery
• Sleep well to reduce variation from fatigue

What happens with the result

Results are used for employer occupational health requirements and for tracking each worker's hearing over time. If a significant change appears, a doctor advises on hearing protection, reducing exposure time, or specialist referral.

The most effective protection is reducing noise at source, using hearing protection correctly and testing at the recommended interval.